System for applying a working pressure to a content of a pressure package with the aid of a propellant

ABSTRACT

A system for applying a working pressure on a content of a pressure package (A) with the aid of a propellant, the system being provided with: a pressure package (A) and a gas supply device (B) comprising a pressure controller ( 2 ) and a high-pressure chamber for storage of the propellant, the gas supply device (B) being provided with a feed-through connecting the high-pressure chamber and the pressure controller to enable propellant to flow from the high-pressure chamber ( 3 ) to the pressure controller, the pressure controller being further arranged to control the working pressure on the content of the package with the aid of the propellant on the basis of a predetermined reference pressure, the gas supply device being furthermore provided with a movable member ( 5 ) which can be brought at least into a control position and into a neutral position, while the movable member in the control position clears the feed-through to enable control of the working pressure, and the movable member in the neutral position blocks the feed-through.

The invention relates to a system for applying a working pressure to acontent of a pressure package with the aid of a propellant, the systembeing provided with: a pressure package and a gas supply devicecomprising a pressure controller and a high-pressure chamber for storageof the propellant, the gas supply device being provided with afeed-through connecting the high-pressure chamber and the pressurecontroller for supplying propellant from the high-pressure chamber tothe pressure controller, the pressure controller being further arrangedto control the working pressure on the content of the pressure packagewith the aid of the propellant on the basis of a reference pressure.

Such a system is known per se. Typically, the known systems are arrangedfor, shortly after the manufacture of the pressure package with thecontent, providing a working pressure on the content with the aid of thepropellant. However, after a working pressure has been provided; it maytake a long time yet before the content is to be expelled from thepressure package under the influence of the working pressure. In fact,it may be that the pressure package with the content, as a product, isstill to be traded, transported, possibly stored, sold, etc., before theproduct is eventually put to use. To prevent the initially appliedworking pressure from decreasing in the period between the provision ofthe working pressure and the use of the product, for instance as aresult of diffusion of propellants through pressure package material,the pressure package material should be of a very high quality. As aconsequence, the required pressure package material is of an expensivequality. The protracted exertion of the working pressure on the contentand inner walls of the pressure package can moreover have adverseeffects both on the content and on the pressure package.

The object of the invention is to provide a system that meets at leastone of the above-mentioned disadvantages.

The object contemplated is achieved with a system according to theinvention which is characterized in that the gas supply device isfurther provided with a movable member which can be brought at least ina control position and in a neutral position, while the movable memberin the control position clears the feed-through to enable control of theworking pressure, and the movable member in the neutral position blocksthe feed-through, so that control of the working pressure is thenimpossible.

In use, the propellant can be included in the high-pressure chamber witha relatively high main pressure when the movable member has been broughtin a neutral position. The movable member then blocks the feed-throughsituated between the pressure chamber and the pressure controller. Atany time to be chosen freely, the movable member can be brought into thecontrol position. In that case, the feed-through situated between thepressure chamber and the pressure controller is cleared to enable thepropellant to flow from the high-pressure chamber to the pressurecontroller. As a result of the relatively high pressure in thehigh-pressure chamber, at least a part of the propellant then flows fromthe high-pressure chamber via the feed-through to the pressurecontroller for controlling a working pressure on the content of thepressure package. As stated, the time at which a user decides to applythe working pressure to the content of the pressure package is to bechosen freely. This means that the working pressure can for instance beprovided shortly before use of the content of the pressure package.Since in the system according to the invention it is not necessary forthe working pressure to be applied to the content from the time ofmanufacture of the pressure package with the content, the adverseeffects of the working pressure on the content and/or the pressurepackage can at least partly be avoided. Also, less high requirements canbe imposed on the pressure package materials.

Optionally, the control of the working pressure can be set out ofoperation by bringing the movable member back into the neutral position.In that case, if any part of the content of the pressure package flowsout, the working pressure on the content of the pressure package is notsustained by the propellant. An additional advantage is that in thatcase, when the working pressure decreases, a high-viscous content willnot of itself readily leave the pressure package through, for instance,an outflow opening which is not closed.

A particular embodiment of the system according to the invention ischaracterized in that the movable member can further be brought in afilling position, while the movable member in the filling positionestablishes a fluid communication between the high-pressure chamber andan inlet of the system to enable the high-pressure chamber to be filledwith propellant, while the movable member in the filling position inaddition blocks the feed-through.

For such a system, it is not even necessary for the propellant to beincluded in the pressure chamber already during the manufacture of thesystem. In a stage after the manufacture of the system, the propellantcan be included in the pressure chamber from, for instance, a supplycontainer, by connecting the supply container to the fluidcommunication. It is even possible to replenish the pressure chamber ifthis should prove necessary during use.

Preferably, in the control position, the movable member blocks the fluidcommunication. This prevents the supply container from obtaining adirect fluid communication with the pressure controller.

Further, preferably, the movable member blocks the fluid communicationin the neutral position as well. This means that it is possible toposition the movable member such that both the feed-through and thefluid communication are blocked. This may be favorable for periods inwhich it is not necessary for the pressure chamber to be filled orreplenished and it is not necessary for the working pressure on thecontent of the pressure package to be sustained. Such a period canoccur, for instance, during storage and/or transport.

Preferably, the movable member comprises a rod which is movable in axialdirection. The rod can comprise a first and a second end, with the firstend of the rod, in the neutral position, closing off the feed-through.Preferably, furthermore, in the neutral position, a circumferentialsurface of the first end of the rod situated substantially parallel tothe axial direction makes contact with an inner wall of the feed-throughsituated substantially parallel to the axial direction, and therebycloses off the feed-through. This provides the advantage that thefeed-through and the first end of the rod will each have predetermineddimensions which remain at least substantially constant during the useof the system. Tearing of the feed-through and/or wear of the first endof the rod is highly unlikely and therefore the closure will possess anat least virtually constant quality. As a consequence, the position ofthe rod relative to the feed-through in the neutral position will hardlychange, if at all, during use, which will facilitate the use of thesystem as regards placing the movable member in the neutral position andpossibly also in the filling position, compared with a situation wherethe feed-through can vary in dimensions and the closure is dependent onthe exact position of the movable member. In fact, the exact positiondoes not need to be the same when the dimensions of the feed-through canincrease during use as a result of, for instance, tearing, indentationand the like.

The invention further relates to a gas supply device for use in such asystem.

The invention is presently elucidated with reference to a drawing. Inthe drawing:

FIG. 1 shows a first embodiment of a system according to the invention;

FIG. 2 shows a second embodiment of a system according to the invention.

FIG. 1 shows a system 1 for applying a working pressure to a content ofa pressure package with the aid of a propellant. To that end, the system1 is provided with: a pressure package A and a gas supply device Bcomprising a pressure controller 2 and a high-pressure chamber 3 forstorage of the propellant. The gas supply device B is provided with afeed-through 4 which connects the high-pressure chamber 3 and thepressure controller 2 to enable the propellant to flow from thehigh-pressure chamber 3 to the pressure controller 2. The feed-through4, in many cases, is a prefabricated feed-through, that is, afeed-through which is already present before the first use of thesystem. The pressure controller 2 is further arranged, on the basis of areference pressure, to control the working pressure on the content ofthe package A with the aid of the propellant. This will be described inmore detail hereinbelow. The gas supply device B is further providedwith a movable member 5 which can be brought at least in a controlposition and in a neutral position. In the control position, the movablemember clears the feed-through 4 to enable control of the workingpressure. In the neutral position, the movable member blocks thefeed-through, so that control of the working pressure is thenimpossible. In the embodiment shown in FIG. 1, the movable member 5 forthat purpose comprises a rod 6, which is movable in axial direction. Rod6 comprises a first end 7. In a neutral position of the rod 6, the firstend 7 closes off the feed-through 4. In the neutral position, morespecifically, a circumferential wall of the first end 7 of the rodsituated substantially parallel to the axial direction makes contactwith an inner wall of the feed-through situated substantially parallelto the axial direction, thereby closing off the feed-through.Preferably, the circumferential wall and the inner wall are each ofcylinder-shaped design. In FIG. 1, the movable member 5 is shown in theneutral position. In the example shown, the gas supply device B isfurther provided with a housing 8, which is included in thehigh-pressure chamber 3. A portion of the movable member 5 is surroundedby the housing 8. Rod 6 is further provided with a second end 9. Thesystem is further provided with a passage 10, situated between thepressure chamber 3 and an ambient space O of the system, which caneffect a fluid communication between the pressure chamber 3 and theambient space O. In the control position and in the neutral position,the rod 6 has its second end 9 extending through the passage 10 andthereby closes off this passage 10. The second end of the rod 6 isprovided with a pull element 11, with which the movable member 5, 6 ismovable into the control position.

The system works as follows. As a starting point, the movable member 5,6 is in the neutral position, as drawn in FIG. 1. The first end 7 of therod 6 then closes the feed-through 4. In use, propellant under highpressure is contained in the high-pressure chamber 3. In the conditionshown, this propellant cannot flow through the feed-through 4 to thepressure controller 2. The pressure controller 2, whose operation isfurther explained hereinbelow, therefore cannot control the workingpressure on the content of the package with the aid of the propellant.In other words, in the neutral position, no propellant can be suppliedfrom the high-pressure chamber 3 to the pressure package A for applyinga working pressure to the content of the pressure package A. Controllingthe working pressure is then impossible.

When with the aid of the propellant a working pressure is to be appliedto the content of the pressure package, the movable member is broughtinto the control position. To that end, the pull element 11 is pulled inthe direction of arrow R. In the control position, the movable member 5,6 clears the feed-through 4 to enable control of the working pressure.In other words, it is then possible for the propellant contained in thehigh-pressure chamber 3 to flow through the feed-through 4 to thepressure controller 2. The pressure controller 2 is described at lengthin WO 99/62791, shown in detail in FIG. 1 of this reference anddescribed in detail in this reference in the description of FIG. 1.Accordingly, hereinbelow, the operation of the pressure controller 2will be discussed only briefly. The pressure controller is arranged, onthe basis of a predetermined reference pressure, to control the workingpressure on the content of the package with the aid of a propellant. Theworking pressure is a pressure to be kept substantially constant. Tothat end, the pressure controller 2 is provided with a referencepressure chamber 16 in which, for obtaining the reference pressure, forinstance a gas is included. The pressure controller 2 is furthermoreprovided with a closing member 17, movable relative to the referencepressure chamber 16, which in this example is designed as a plunger. Theplunger 17 is provided with a sealing ring 18 for preserving a gasincluded in the reference pressure chamber 16 with the referencepressure. The pressure controller 2 is further provided with acylinder-shaped cap 19 which, together with the plunger 17, bounds thereference pressure chamber 16. The cap 19 is provided with athrough-going recess 20 for effecting a gas communication between inletopening 13 of the pressure package A and a space 21 included between theplunger and a closure 22 closing off the cap 19. For establishing a gascommunication between the through-going recess 20 and the pressurepackage A, a part of the pressure controller 2 is included in thecylinder 42 which at one end adjoins a partition wall S situated betweenthe pressure package A and the gas supply device B, and at another endis also closed off by the closure 22. In the partition wall S there isan inlet opening 13 which, at an end proximal to the gas supply device,terminates within the cylinder 42 and at an end remote from the gassupply device terminates in the pressure package A. The through-goingrecess 20 terminates on one side in the cylinder 42 and on the otherside in the space 21. Closure 22 is further provided with a pressurecontrol passage 23 in which a stem 24 of the plunger 17 is received witha close fit. Stem 24 of the plunger 17 is provided with an annularrecess 25 to enable effectuation of a gas communication between thehigh-pressure chamber 3 and the space 21. Stem 24 of the plunger 17 canmove in the pressure control passage 23 in the direction of arrow R,such that a gas communication between the space 21 and the high-pressurechamber 3 is effected. When there is a gas communication, the sealingring 26 extends in the annular recess 25, thereby leaving open a fluidpath between the sealing ring 26 and the stem 24. The plunger 17 canmove in the direction of arrow “a” in such a manner that the gascommunication between the space 21 and the high-pressure chamber 3 isclosed again. In FIG. 1 the gas communication is closed, since thesealing ring 26 presses against the cylinder wall of stem 24. Theeffectuation of a gas communication between the space 21 and thehigh-pressure chamber 3 is determined by the position of stem 24relative to the sealing ring 26. The closure of the gas communicationbetween the space 21 and the high-pressure chamber 3 is therefore takencare of by the sealing ring 26 arranged in the pressure control passage23. In use, the reference pressure in the reference pressure chamber 16will be chosen to be slightly lower than the working pressure to beexerted on the content of the pressure package A.

The pressure controller 2 controls as follows. When the pressure in thepressure package A is lower than the reference pressure in the referencepressure chamber 16, the pressure in the space 21 will also be lowerthan the reference pressure in the reference pressure chamber 16. As aconsequence, the plunger 17 moves in the direction of arrow R, at leastwhen the reference pressure in the reference pressure chamber 16 ishigher than the pressure in the space 21. It should be noted that a highpressure of the gas in the high-pressure chamber 3 as exerted on asubsurface 27 will hardly make any contribution to the position of theplunger 17 since this subsurface 27 is very small. As said, when plunger17 with the stem 24 moves in the direction of arrow R, a gascommunication between the space 21 and the high-pressure chamber 3 iseffected in the pressure control passage 23 via the annular recess 25.The propellant operatively contained in the high-pressure chamber willflow via this gas communication to the space 21. Via the through-goingrecess 20 provided in the cap 19, the propellant will flow via inletopening 13 to the pressure package A. When in the pressure package A thepressure is slightly higher than the reference pressure in the referencepressure chamber 16, the plunger 17 will move in the direction of arrow“a”. The gas communication between the space 21 and the high-pressurechamber 3 is thereby closed off by the contact between the sealing ring26 and the stem 24. The operating pressure prevailing in the pressurepackage A is therefore slightly higher than the reference pressure inthe reference pressure chamber 16. It is now possible to bring themovable member 5, 6 in the neutral position again by pushing the handle11 in the direction of arrow “a”. The first end 7 of the rod 6 will thenproject through the feed-through 4 again, and thereby close off thefeed-through 4. It is then no longer possible to control the workingpressure in the pressure package A when, for instance, owing to a user,a part of the content has flowed from the pressure package and thepressure in the pressure package has thereby been lowered. In otherwords, when the movable member is in the neutral position, then, uponopening of the pressure package, the operating pressure will not becontrolled. Should a user, after having closed the pressure package Aagain, wish to apply the working pressure to the remainder of thecontent of the pressure package A again after all, the user should bringthe movable member in the control position by pulling the handle 11 inthe direction of arrow R. The rod 6 then moves in the axial direction ofthe rod, in the direction of arrow R, and thereby clears thefeed-through 4. It is then possible again for propellant to flow fromthe high-pressure chamber 3 through the feed-through 4 to the pressurecontroller 2. The pressure controller 2 can then control the workingpressure on the content of the pressure package A again in the mannerdescribed above.

In the embodiment shown in FIG. 1, the movable member 5, 6 is fixable inthe control position. To that end, the rod is provided with first fixingmeans 51 on a part of the rod 6 situated between the first end and thesecond end 9 thereof. The pressure chamber 3 is provided with secondfixing means 52. The first and second fixing means 51, 52 can cooperatefor the purpose of keeping the movable member 5, 6 in the controlposition. The first fixing means 51 comprise, for instance, a part 53which is flexible and projects with respect to the rod 6. The secondfixing means 52 comprise, for instance, a ring 54 arranged around thecircumferential surface of the rod 6 in such a way that upon placementof the rod 6 in the control position, the flexible part 53 is clampedbetween the ring 54 and the rod 6 for fixing the rod 6. The first fixingmeans 51 shown will curl up upon movement of the rod 6 into the controlposition and be locked, clamped between the ring 54 and acircumferential surface of the rod 6. However, it is also possible touse first fixing means which, for instance, are indented to some extentwhen the rod 6 is brought into the control position. When the rod 6, ifso desired, is brought into a neutral position by pushing the rod 6 inthe direction of arrow “a”, the first flexible parts 51 can be releasedfrom the clamped position between the circumferential surface of the rod6 and the ring 54.

In the embodiment shown by way of example in FIG. 1, the movable member6 can further be brought into a filling position for the purpose offilling the high-pressure chamber 3 with propellant. In the fillingposition, the movable member 5 effects a fluid communication between thehigh-pressure chamber 3 and the ambient space O of the system to enablethe high-pressure chamber 3 to be filled with propellant. In the fillingposition, the movable member further blocks the feed-through 4. The gassupply device B in this example is provided with a spring 63 whichprevents the possibility of the movable member ending up in the fillingposition of itself. For bringing the movable member 5 from the controlposition into the filling position, a second end 9 of the rod 6 ispushed against the spring force of the spring 63, in the direction ofarrow “a”. For the purpose of filling, the rod 6 in this example isprovided with a channel 60 which extends from a first position 61adjacent the second end 9 on the surface of the rod 6, through the rod 6as far as a second position in the direction of the first end 7 on thecircumferential surface of the rod 6. The distance between the firstposition 61 and the second position 62 is such that when the rod 6 hasbeen brought into the filling position, the first position is situatedoutside the high-pressure chamber 3 and the second position is locatedwithin the high-pressure chamber 3. Furthermore, the distance is suchthat when the rod 6 has been brought into the neutral position or intothe control position, the first position 61 and the second position 62are situated outside the high-pressure chamber 3. In other words, whenthe rod 6 has been brought into the filling position, the channel 60constitutes the fluid communication between the high-pressure chamber 3and an inlet I of the system to enable the high-pressure chamber 3 to befilled with propellant. In use, typically, for filling the high-pressurechamber 3, a supply container, not shown, will be connected to thechannel 60. The inside of the housing 8 has a continuous fluidcommunication with the high-pressure chamber 3. This makes it possiblefor the high-pressure chamber 3 to be filled with propellant in thefilling position. In such an embodiment, in the control position, themovable member 5, 6 blocks the fluid communication between thehigh-pressure chamber 3 and the inlet I of the system. As already said,the movable member 6 clears the feed-through 4 in the control position.The movable member 6 in the filling position effects the fluidcommunication between the high-pressure chamber 3 and an inlet I of thesystem, and in the filling position blocks the feed-through 4. In theneutral position of rod 6, as shown in FIG. 1, both the feed-through 4and the fluid communication between the high-pressure chamber 3 and theinlet I are blocked.

The spring 63 and at least a part of the movable member 5, 6 aresurrounded by the housing 8. The ring 54, mentioned earlier, isaccommodated in the housing 8. The spring 63 sits around the rod 6, andthe inner side of the housing 8 is provided with a collar K againstwhich the spring 63 sits. Housing 8 is further provided with a firstopening O.1 and a second opening O.2. The first end 7 of the rod 6extends through the first opening O.1. The second opening O.2 links upwith the passage 10. Rod 6 is further provided with a thickening Dsituated between the first end 7 and a second end 9, such that the rodis confined in the housing 8. The thickening D is such as to fit neitherthrough the first opening O.1 nor through the second opening O.2 of thehousing 8. It will be clear that the feed-through 4 is provided with asuitable sealing ring 4.1. It will further be clear that the passage 10is provided with a suitable sealing ring 10.1.

The system may be of two-part design. A first part can then comprise thepressure package and a second part can comprise the gas supply device B.As shown in FIG. 1, the first part and the second part can be integrallyconnected with each other. It is also possible, however, to market thepressure package A separately from the gas supply device B with thepressure controller. In such an embodiment of the system, the first partis connectable with the second part. The pressure package A can also,for instance, be designed for single use whereas the gas supply device Bis designed to be used many times. In that case, the first part and thesecond part are detachably connectable with each other.

FIG. 2 shows a gas supply device B which is connectable with a pressurepackage A. Equal reference numerals here refer to equal parts such asthese have been discussed in the discussion of the embodiment shown inFIG. 1. In this case, the system is of two-part design. The first partthen comprises the pressure package A, not shown in FIG. 2, and thesecond part then comprises the gas supply device B shown in FIG. 2. Inthis embodiment, it is optionally also possible for the first part andthe second part to be detachably connectable with each other. Thus, thesecond part, that is, the gas supply device B, can first be used with afirst pressure package and then be used with a second pressure package,possibly to be subsequently used with the first pressure package again.The high-pressure chamber 3 in this embodiment is filled with highpressurized propellant. The operation of the embodiment shown in FIG. 2further corresponds broadly to the operation of the embodiment shown inFIG. 1. A few particular aspects of the gas supply device B shown inFIG. 2 will be discussed hereinbelow. In this case, the gas supplydevice B comprises a pressure controller 2 included outside thehigh-pressure chamber 3. The high-pressure chamber 3 comprises acircularly symmetrical vessel V, with which propellant is prevented fromdiffusing through the walls (bold-type hatched) of the vessel V in thedirection of the high-pressure controller 2.

In the example according to FIG. 2, the high-pressure controller 2 isreceived in a cylinder-shaped recess C of an outer wall W of the vesselV. The pressure controller 2 comprises a cap 19, situated at a first endC.1 of the cylinder-shaped recess C, by means of which the recess C isclosed off. The cap 19 is provided with a cylinder jacket 80 extendingin the direction of the vessel V. In this cylinder jacket 80, a plunger17 is accommodated. The space between the cap 19, the cylinder jacket 80and the plunger 17 forms the reference chamber 1. In this example, thecap 19 closes off the cylinder-shaped recess C. The cylinder jacket 80does not have its entire outer circumference abutting against thecylinder-shaped inner wall of the cylinder-shaped recess C, that is,there is a channel 81 present between the outer walls of the cylinderjacket 80 and the inner walls of the cylinder-shaped recess C. Further,the cylinder jacket 80 extends to a point spaced from a bottom C2situated at a second end C.2 of the cylinder-shaped recess C. In thebottom C2 there is the pressure control passage 23 with which,analogously to the pressure control passage 23 shown in FIG. 1, a gascommunication can be established between the space 21 and thehigh-pressure chamber 3 when the movable member 6 has been brought inthe control position.

The cap 19 is provided with a recess (not shown) which extends throughthe cap from a position contiguous to the channel 81 as far as theoutflow opening 13. Between the space 21 and the outflow opening 13,therefore, a continuous gas communication is present.

Through movement of movable member 5 in the direction of arrow “a”, themovable member is brought in the neutral position, since a fluidcommunication between the pressure controller 2 and the high-pressurechamber 3 is then closed off. In FIG. 2, the movable member 5 is in thecontrol position, since there is a gas communication between thehigh-pressure chamber 3 and an end 23.1 of the pressure control passage23.

Naturally, it is also possible for the system to comprise a supplycontainer with propellant. In that case, this supply container can beconnected to a portion situated outside the high-pressure chamber 3 of amovable member 5, 6 which can be brought into a filling position. Thesupply container is then connected to the inlet I.

The pressure package may be provided with a content which is expelledunder pressure from the pressure package A through an outlet opening(not shown), situated, for instance, opposite the pressure controlleropening 13. Thus, the pressure package A can, for instance, have aviscous liquid as content. This viscous liquid can for instance comprisea cement. To be considered here, for instance, is a silicone cement oran acrylic cement. The gas supply device B, for instance such as it isshown in FIG. 2, can then be included in a silicone paste gun.

The invention is not limited in any way to the exemplary embodimentshown. Thus, the movable member 5 can also comprise a part of thepressure chamber wall. The gas supply device B can for instance bedesigned such that the rod, in the filling position, through depressionwith the aid of a supply container outlet, ends up entirely within thepressure chamber, no longer closes off passage 10 and in this wayestablishes the second fluid communication. The spring and the housingmay be arranged to keep the movable member in the neutral position withthe spring relaxed. The flexible parts 53 may then also be designed tospring.

The fixation of the movable member, incidentally, will preferably betemporary. However, embodiments in which the movable member is fixed asingle time and definitively are also conceivable and are alsounderstood to belong to the invention.

A lock for one or all possible positions of the movable member can alsobe situated outside the pressure chamber, so that a user can operatesuch lock by hand. In that case, the position of the movable member canbe clearly visible to a user.

The system may further be provided with a chamber which is openableprior to a first use, which chamber is included in the feed-through. Useis now understood to mean the provision of the working pressure from thegas supply device for the first time. The first end of the rod can inthat case be provided with an opener facing the openable wall, foropening the openable wall before the system is brought into the controlposition for the first time. The openable wall can be an additionalsealing capable of preventing leakage of propellant from the gas supplydevice before the gas supply device is taken into use. The openerreferred to can comprise a pointed part and the openable wall can bedesigned to be pierceable with the pointed part.

All such variants are understood to fall within the framework of theinvention.

1. A system for applying a working pressure to a content of a pressurepackage with the aid of a propellant, the system comprising: a pressurepackage configured to hold a content to be delivered, a high-pressurechamber configured to hold the propellant, a pressure controllerconnected to the high pressure chamber by a feed-through and configuredto control the working pressure applied to the content of the pressurepackage with the aid of the propellant, the working pressure beingdetermined on the basis of a predetermined reference pressure, and amovable member positionable in at least a control position and a neutralposition; wherein, the movable member, in the control positions, clearsthe feed-through to enable control of the working pressure, and themovable member, in the neutral positions, blocks the feed-through, sothat control of the working pressure is then impossible.
 2. A systemaccording to claim 1, characterized in that the movable member isfixable in the control position.
 3. A system according to claim 1,characterized in that the movable member can further be brought into afilling position, whereby the movable member in the filling positioneffects a fluid communication between the high-pressure chamber and aninlet of the system to enable the high-pressure chamber to be filledwith propellant, while further the movable member in the fillingposition blocks the feed-through.
 4. A system according to claim 3,characterized in that the movable member in the control position blocksthe fluid communication.
 5. A system according to claim 3, characterizedin that the movable member blocks the fluid communication in the neutralposition as well.
 6. A system according to claim 1, characterized inthat the gas supply device is provided with a spring which prevents thepossibility of the movable member of itself ending up in the fillingposition.
 7. A system according to claim 1, characterized in that themovable member comprises a rod, which rod is movable in an axialdirection.
 8. A system according to claim 7, characterized in that therod comprises a first end, the first end of the rod in the neutralposition closing off the feed-through.
 9. A system according to claim 8,characterized in that, in the neutral position, a circumferentialsurface of the first end of the rod situated substantially parallel tothe axial direction makes contact with an inner wall of the feed-throughsituated substantially parallel to the axial direction, and therebycloses off the feed-through.
 10. A system according to claim 9,characterized in that the circumferential wall and the inner wall areeach of cylinder-shaped design.
 11. A system according to claim 3,characterized in that the first end of the rod closes off thefeed-through in the filling position as well.
 12. A system according toclaim 7, characterized in that the rod is provided with a second end andthat the system is provided with a passage, situated between thehigh-pressure chamber and the inlet of the system, which can effect thefluid communication between the pressure chamber and the inlet, whilethe rod in the control position and in the neutral position extends bythe second end thereof through the passage and thereby closes off thispassage.
 13. A system according to claim 11, characterized in that therod is provided with a channel which extends from a first positionadjacent the second end on the surface of the rod as far as a secondposition in the direction of the first end on the circumferentialsurface of the rod, while the distance between the first position andthe second position is such that when the rod has been brought into thefilling position the first position is situated outside the pressurechamber and the second position is situated inside the pressure chamber,and such that when the rod has been brought into the neutral position orinto the control position, the first position and the second positionare situated outside the pressure chamber.
 14. A system according toclaim 12, characterized in that the rod is provided with first fixingmeans on a part of the rod situated between the first and the secondend, and that the pressure chamber is provided with second fixing means,the first and the second fixing means being capable of cooperating forthe purpose of keeping the movable member in the control position.
 15. Asystem according to claim 14, characterized in that the first fixingmeans comprise a part which is flexible and projects with respect to therod, and the second fixing means comprise a ring arranged around thecircumferential surface of the rod, in such a way that upon placement ofthe rod in the control position, the flexible part is clamped betweenthe ring and the rod for fixing the rod.
 16. A system according to claim8, characterized in that the rod has a second end of the rod providedwith a pull member with which the movable member is movable into thecontrol position.
 17. A system according to claim 8, characterized inthat the rod has a second end of the rod pushable in a direction of thepressure chamber for placing the movable member in the control position.18. A system according to claim 1, comprising a housing which isincluded in the high-pressure chamber and by which at least a part ofthe movable member is surrounded.
 19. A system according to claim 18,characterized in that the housing is provided with a first and a secondopening, the first end of the rod extending through the first opening,and the second opening linking up with the passage.
 20. A systemaccording to claim 1, characterized in that the system is of multipartdesign, with a first part comprising the pressure package, and a secondpart comprising the pressure controller and the high-pressure chamber.21. A system according to claim 20, characterized in that the first partand the second part are integrally connected with each other.
 22. Asystem according to claim 20, characterized in that the first part andthe second part are connectable with each other.
 23. A system accordingto claim 22, characterized in that the first part and the second partare detachably connectable with each other.
 24. A system according toclaim 1, characterized in that the system is configured to deliver aviscous liquid.
 25. A system according to claim 24, characterized inthat the viscous liquid comprises a cement.
 26. A system according toclaim 7, characterized in that the system is provided with a wallopenable prior to use, which wall is included in the feed-through, whilea first end of the rod is provided with an opener facing the openablewall for opening the openable wall before the system is brought into thecontrol position for a first time.
 27. A system according to claim 26,characterized in that the opener comprises a pointed part and that theopenable wall is designed to be pierceable with the pointed part.
 28. Agas supply device as described in claim
 1. 29. An article, comprising: aworking chamber configured to hold, at a working pressure, a material tobe delivered, a propellant reservoir configured to hold a propellant ata pressure higher than the working pressure, a pressure controllerconnected to the propellant reservoir by a feed-through and configuredto use propellant that has passed along the feed-through from thepropellant reservoir to the pressure controller to maintain the workingpressure of the material to be delivered, and a movable memberselectively positionable between a neutral position and a workingposition; wherein, the movable member, when in the neutral position,blocks the passage of propellant along the feed-through from thepropellant reservoir to the pressure controller and, when in the workingposition, allows the passage of propellant along the feed-through fromthe propellant reservoir to the pressure controller.
 30. The article ofclaim 29, wherein the pressure controller comprises a pressure controlchamber configured to hold a fluid having a reference pressure and theworking pressure is determined by the reference pressure.